The present invention relates to manufacturing methods, and more particularly, to production line manufacturing methods which employ computer controls.
In a build-to-order production facility, a number of components are placed on a single production line but receive different manufacturing operations. A typical example of such a build-to-order production facility is an automobile manufacturing plant, where automobile vehicle bodies are placed on a single production line but receive different manufacturing operations. For example, such vehicle bodies may be painted different colors in a paint facility on the production line, receive a different engine, a different interior, and so on.
In such plants, each individual component, such as an automobile vehicle body, has been ordered by a purchaser or dealer and must carry information which identifies the configuration of the particular vehicle body and the custom manufacturing operations to be performed on that vehicle, such as color, vehicle interior components, vehicle engine specifications, and the like. Typically, such information is in the form of a random identifier, which may be simply a number, which has associated with it in the factory computer system the particular specifications. Such identifying information is placed on a paper label which is attached to a vehicle body. When the vehicle body is placed on a production line, this paper label is scanned and the random identifier number is fed to the factory system so that the factory system is aware of the location of the vehicle body. Thus, the identification tag enables the factory system to identify the location of a particular vehicle body within the plant and to ensure that the necessary manufacturing operations are performed upon it to result in the desired a configuration.
With such systems, it is impracticable to change the "identity" (i.e., the specific color, interior, engine and the like) of a vehicle body once it has been placed on the production line and identified with the paper label. While it is possible to remove the paper identification method label and replace it with one carrying different information, to effect such a change would require slowing down or stopping the production line, or removing the vehicle body from the line. A further disadvantage is that the print on the tag may smear or otherwise degrade as successive manufacturing operations are performed upon the associated vehicle body.
It is also known to use an RFID (radio frequency identification) tag, which is a hang tag having a microchip embedded within it which carries vehicle identification information. However, such RFID tags often fail, resulting in a loss of "identity" of the associated vehicle body.
Furthermore, in order to optimize use of the production line and maximize output, it is sometimes necessary to change the order in which such vehicle bodies are sequenced on a production line. Accordingly, there is a need for a method and system for "rearranging" the order in which vehicle bodies are sequenced on a production line with minimal disruption of the operation of the line. Preferably, such a method and system would eliminate the need for replacing the paper labels or physically removing the bodies from the production line and reinserting them on the production line in a desired sequence.